Certainly paleontologists have found samples of an extremely small fraction, only, of the earth's extinct species, and even for groups that are most readily preserved and found as fossils they can never expect to find more than a fraction.

I have a debt, a loyalty to the museum; the best place for me to do what I wanted to do.

The earliest and most primitive known members of every order already have the basic ordinal characters, and in no case is an approximately continuous sequence from one order to another known. In most cases the break is so sharp and the gap so large that the origin of the order is speculative and much disputed.

Recognition of this kinship with the rest of the universe is necessary for understanding him, but his essential nature is defined by qualities found nowhere else, not by those he has in common with apes, fishes, trees, fire, or anything other than himself.

Man is the result of a purposeless and natural process that did not have him in mind

A rill in a barnyard and the Grand Canyon represent, in the main, stages of valley erosion that began some millions of years apart.

Splitting and gradual divergence of genera is exemplified very well and in a large variety of organisms.